This comprehensive research proposal by Childrens Hospital of Los Angeles (CHLA) is deisgned to improve the treatment of children with cancer by conducting clinical investigations as a member of Childrens Cancer Study Group (CCSG) and by independently conducting other research which is directly related to the mission of CCSG. CHLA is a major pediatric referral center for the Pacific Southwest and has one of the largest pediatric oncology services in the nation. An interdepartmental program has developed at CHLA which involves basic and clinical scientists and has evolved into a multidisciplinary model for the management of pediatric cancers with representation from the disciplines of Pathology, Surgery, Radiation Therapy, Radiology, Nuclear Medicine, Virology, and Hematology-Oncology. The participation of the investigators of CHLA in CCSG enables quantitative comparative clinical investigations aimed at establishing the best mode of any cancer therapy. The unique resources of CHLA permit the development of new therapeutic approaches as background for groupwide application. These include participation in the National Cancer Institute Phase I Working Group and the Late Effects Study Group, as well as research aimed at the evaluation of new dose schedules and combinations of established agents predicted by in vitro and in vivo pharmacological studies, immunological characterization of selected neoplasms, intensive chemotherapy in the protected environment, optimum nutritional support in childhood malignancies, and approaches to psychosocial rehabilitation of the pediatric cancer patient and family. A network of community physicians participates in the CCSG Cancer Control Program for Clinical Cooperative Groups under the sponsorship of CHLA which enables the use of optimal therapy in children who are not referred for primary care. Proposed continuation of the comprehensive program at CHLA will seek as its ultimate goal an integrated therapeutic and investigative approach to childhood cancer.